Large numbers of containers, particularly beverage cans, are conventionally opened by pulling off a tear strip which is removable together with the attached ring tab. The severed tear strip with attached tab may be carelessly discarded with undesirable consequences, such as litter and a hazard to bare feet. Moreover, many cans with easy-open ends of this sort are made of aluminum alloys which can be produced with less expenditure of energy through recycling than from the original ore, and the metal in the tear strip and tab are more readily collected and recycled if the tear strip and tab remain with the can body after opening of the can.
The container industry is highly competitive and has long made serious efforts to design easy-open can ends, particularly of the kind used to contain beer and carbonated beverages, so that the tear strips and tabs could be secured non-detachably while still remaining convenient to operate and use, and free of substantial cost penalties. These efforts have produced many designs, but none before the present invention appears to have provided a solution of the problem unaccompanied by one or more difficulties which make the design as a whole commercially unsatisfactory.